Fig. 3.

Monocyte and DC subsets from older individuals are impaired in interferon response factor 7 (IRF7) phosphorylation. Human PBMCs from the blood of younger (age, 24–36 years; n = 11) and older (age, 67–83 years; n = 11) healthy donors were either stimulated with LPS/IFN-γ or CLO97, a TLR7/8-specific agonist, or transfected with a RIG-I-specific 3p-hpRNA ligand. For unstimulated and control conditions, refer to Fig. 1. a Representative flow plot for data presented in b–d. Using these plots, the fold change of pIRF7 MFI was calculated using the unstimulated as the control. b–d PBMCs were either stimulated with LPS/IFN-γ, CLO97, or RIG-I agonist or left unstimulated for 15 min or 24 h. Cells were permeabilized, fixed, and stained for phosphorylated IRF7 transcription factor. After gating on monocyte and DC subsets, the geometric mean intensity (MFI) was measured using Phosflow cytometry. Data are means. *p < 0.05, **p < 0.01, ***p < 0.001, unpaired, non-parametric Mann–Whitney U test